Reports
Prevalence and epidemiology of onychomycosis in patients visiting physicians’ offices: A multicenter Canadian survey of 15,000 patients

https://doi.org/10.1067/mjd.2000.104794Get rights and content

Abstract

A prospective, multicenter study to determine the epidemiology of onychomycosis was performed in the offices of 3 dermatologists and 1 family physician in Ontario, Canada. In the sample of 15,000 patients, abnormal-appearing nails were observed in 2505 persons (16.7%). There were 1199 patients (8%) with toenail or fingernail onychomycosis confirmed on mycologic examination, with 1137 patients (7.6%) who had only pedal onychomycosis, 40 patients with toenail and fingernail onychomycosis (0.27%), and 22 patients (0.15%) with only fingernail onychomycosis. The condition was more common in male patients (P <.0001) and older persons (P <.0001). The ratio of onychomycosis in toenails/fingernails was 19:1. When onychomycosis was present in toenails, the ratio of distal/lateral subungual onychomycosis (DLSO) to white superficial onychomycosis to proximal subungual onychomycosis was 360:59:1. The extent of DLSO in toenails was mild (≤25% nail involvement), moderate (26%-74% disease), and severe (≥75% nail involvement) in 27.6%, 39.9%, and 32.5% of patients, respectively. After adjusting for the age and sex distribution of the general population, the projected rate of onychomycosis in Canada is 6.5% (95% confidence interval [CI], 6.1%-6.9%). The organisms causing toenail onychomycosis were 90.5% dermatophyte, 7.8% nondermatophyte molds, and 1.7% Candida spp. The corresponding organisms causing fingernail onychomycosis were 70.8%, 0%, and 29.2%, respectively. In a large sample of 15,000 patients, abnormal-appearing nails were present in 17% of the sample with mycologic evidence of toenail or fingernail onychomycosis in 8%. The projected prevalence of onychomycosis in Canada is 6.5% (95% CI, 6.1%-6.9%). (J Am Acad Dermatol 2000;43:244-8.)

Section snippets

Patients and methods

Patients visiting the offices of 3 dermatologists and 1 family physician were informed about the project evaluating the prevalence of onychomycosis in Ontario, which is situated in eastern Canada. All consecutive consenting individuals were evaluated. In Canada, the family physician treats all age groups for any medical condition. The dermatologists see patients of all ages and with a wide range of dermatologic disorders.

The evaluation of the feet and sampling of the nails for mycologic

Results and discussion

In this series, 15,000 patients have been evaluated excluding those referred to dermatologists’ offices for the management of nail problems or onychomycosis, and persons who declined to have their nails examined. An advantage of the present study is that clinical evaluation, mycologic sampling, and laboratory analysis were performed by only a limited number of persons, all of whom were highly skilled in these techniques. In addition, processing of the nail sample in the laboratory was carried

Acknowledgements

We thank Dr Lynne Sigler for her consultation on the identification of the Arachnomyces spp.

References (11)

  • AK Gupta et al.

    Antifungals: an overview. Part II

    J Am Acad Dermatol

    (1994)
  • G Achten et al.

    Onychomycosis in the laboratory

    Mykosen

    (1987)
  • AK Gupta et al.

    Antifungals: an overview. Part I

    J Am Acad Dermatol

    (1994)
  • BE Elewski et al.

    Prevalence of onychomycosis in patients attending a dermatology clinic in northeastern Ohio for other conditions

    Arch Dermatol

    (1997)
  • Ghannoum MA, Hajjeh R, Elewski B, et al. Onychomycosis in North America: prevalence, causative organisms, and...
There are more references available in the full text version of this article.

Cited by (0)

Reprints not available from authors.

View full text